Single-pole double-break high-voltage switch assembly

ABSTRACT

A high-voltage single-pole double-break switch assembly characterized by two outer, fixed, diverging, coplanar insulators whose inner adjacent ends are anchored to a base, and whose outer ends are free and carry switch contacts. Intermediate the outer insulators is an inner insulator journaled on the base for rotation about its own longitudinal axis. The inner insulator carries a switch blade whose outer ends simultaneously engage and disengage the switch contacts with rotation of the insulator. With the blade engaging the contacts, the blade and the two outer insulators bound a substantially triangular zone, one apex of which is adjacent the base.

United States Patent Kerr, Jr.

SINGLE-POLE DOUBLE-BREAK HIGH- VOLTAGE SWITCH ASSEMBLY I Dec. 5, 1972 [57] ABSTRACT A high-voltage single-pole double-break switch assembly characterized by two outer, fixed, diverging, coplanar insulators whose innerradjacent ends are anchored to a base, and whose outer ends are free and carry switch contacts. Intermediate the outer insulators is an inner insulator journaled on the base for rotation about its own longitudinal axis. The inner insulator carries a switch blade whose outer ends simultaneously engage and disengage the switch contacts with rotation of the insulator. With the blade engaging the contacts, the blade and the two outer insulators bound a substantially triangular zone, one apex of which is adjacent the base.

4 Claims, 3 Drawing Figures PATENTEDHEB 51912 a 3 6 8 6 6 M 7 a. 2 m 6 a 8 FM 3L .1 Z 8 m u 3 www w. h A 8 a a. 0 3 w a Charles E. Kerr, Jr:

BY INVENTOR a4; aw 2w SINGLE-POLE DOUBLE-BREAK HIGH-VOLTAGE SWITCH ASSEMBLY BACKGROUND ANDSUMMARY OF THE INVENTION This invention p'ertainsto a high-voltage switch assembly,'and more particularly, to such an assembly which is of the single-pole double-break variety.

Prior switch assemblies of the type generally indicated have been characterized by various disadvantages, one of the principal ones of which is that they are normally quite large and bulky and require large and costly structures for supporting them above the ground.

A general object of the present invention, therefore, is to provide a novel single-pole double-break highvoltage switch assembly'which takes care of these problems in. a practical and satisfactory manner.

More. specifically, an object of the invention is to provide such an assembly which is extremely compact, and which requires only a relatively simple and inexpensive structure to support it above the ground.

According to a preferred embodiment of the invention, theproposed switch assembly comprises a base, and three elongated insulators, including a pair of outer insulators and an inner insulator, mounted on the base and diverging from one another(in a common plane) progressing away from the base. The outer insulators are anchored to the base, and the inner insulator is journaled on the base for rotation about its own longitudinal axis. Supported on these three insulators is a switch including a pair of contacts each journaled on a different one of the spaced-apart free ends of the outer insulators, and an elongated blade mounted substantially'centrally intermediate its opposite ends on the free end of the inner insulator. With rotation of the inner insulator, the blade also rotates, producing simultaneous engagement and disengagement of its outer ends with the contacts. With the outer ends of the blade engaging the contacts, the blade and the outer insulators bound a substantially triangular zone, one apex of which is adjacent the base in the assembly.

With the generally triangular planar configuration thus proposed for the switch assembly, a compact overall construction results. In addition, with an apex of this triangular configuration adjacent the base in the assembly, the base can be relatively small in size, and can accommodate mounting of the assembly on a relatively simple and inexpensive and small supporting structure.

DESCRIPTION OF THE DRAWINGS These and other objects and advantages attained by the invention will become more fully apparent as the description which follows is read in conjunction with the accompanying drawings, wherein:

FIG. 1 is a simplified fragmentary perspective view illustrating a multiple-switch installation employing three switch assemblies constructed according to the present invention;

FIG. 2 is an enlarged side elevation illustrating one of the switch assemblies in the installation of FIG. 1; and

FIG. 3 is a simplified view taken along the line 3--3 in FIG. 2, illustrating a blade in the assembly in two different positions.

DETAILED DESCRIPTION OF THE INVENTION Turning now to the drawings, and referring first to FIG. 1, indicated generally at 10 is a multiple-switch installation which forms part of a three-plane high-voltage AC power distribution system. Installation 10 includes three single-pole double-break switch assemblies 12, 14, 16 constructed according to the present invention. In general terms, assemblies 12, 14, 16 are to make or break electrical connections between pairs of power lines in each of the three phases of the system.

.More specifically, each assembly is adapted to make and break such a connection 'between-a pair of power lines simultaneously at a pair of pointsin the lines thus attaining the double-break characterization just mentioned. Switch assembly 12 is interposed between lines 18a, 18b in one phase, switch assembly 14 between lines 20a, 20b in anotherphase, and switch assembly 16 between lines 22a, 22b in the third phase. The particular-power system illustrated herein operates at about 1 15 Kilovolts.

Assemblies 12, 14, 16 are anchored, as will be more fully explained, to a conventional pair of elongated, parallel, substantially horizontal cross arms 24 which are anchored to the tops of a pair of spaced-apart upright poles 26. The cross arms herein are each about 25 feet long, are spaced apart by about 14 inches, and are supported about 25 feet above the ground. Poles 26 are about 20 feet apart. 4

Considering the construction of switch assembly 12 (the other two assemblies being substantially the same), and referring to FIGS. 2 and 3, the assembly includes a base 28, elongated insulators 30, 32, 34, and a switch 36.

Base 28 includes a central portion 28a and a pair of end portions 28b, 28c. Central portion 28a comprises a pair of upright spaced-apart substantially parallel side plates 38 joined together along their upper edges through a substantially horizontal plate 40. Outwardly extending substantially horizontal flange plates, such as plate 42, are joined to the bottom edges of side plates 38, and accommodate mounting of the base (through bolts such as those shown at 44) on cross arms 24.

End portion 28b in the base comprises a pair of spaced-apart parallel side plates 46 joined to the left edges-of plates 38 in FIG. 2, and oriented substantially as shown in the figure. Extending between and suitably joining the upper ends of plates 46 is a plate 48 which slopes downwardly and to the left in FIG. 2 at an angle of about 30 to the horizontal. End portion 280 is similar in construction to end portion 28b, except that the inclinations of its corresponding parts are the reverse of those in end portion 28b. Thus end portion 280 includes spaced-apart side plates 50 corresponding to side plates 46, and a plate 52, corresponding to plate 48, joining upper ends of plates 50. Plate 52 slopes downwardly and to the right in FIG. 2 at an angle of about 30 to the horizontal. The various parts making up the end and central portions of the base preferably are formed of a material such as steel.

Insulators 30, 32, 34 are formed from axial stacks of conventional ceramic insulator dishes, such as dishes 54. These insulators are substantially the same in size,

32 occupy a common vertical plane, indicated at 55 in FIG. 3, and are disposed normal to the planes of plates 48, 52, respectively. It will be noted that the lower ends of insulators 30, 32 in FIG. 2 are positioned relatively closely adjacent one another, and that the insulators diverge progressing upwardly in the figure.

Insulator 34 is disposed substantially centrally intermediate insulators 30, 32, with its longitudinal axis 34a substantially vertical and lying within plane 55. The lower end of insulator 34 in FIG. 2 is mounted on plate 40 in the base through a conventional journal connection indicated generally at 56. Journal connection 56 accommodates rotation of the insulator about axis 34a. A crank 58 is suitably fastened to the journal connection for rotating the insulator. Any suitable means may be provided for operating this crank.

Suitably secured to the upper or free ends of insulators 30, 32 in FIG. 2 are mountings 60, 62, respectively, which are substantially identical in construction. Mountings 60, 62 are shaped substantially as indicated,

and include integral outwardly projecting terminal pads 64, 66, respectively. These mountings are preferably formed, as by casting, from copper.

Switch 36 includes a pair of contact assemblies 68, 70 and an elongated blade 72. Contact assemblies68, 70 are substantially the same in construction, are conventional, and are suitably fastened to mountings 60, 62, respectively. Each of these contact assemblies inclucles a plurality of spaced-apart fingers, or contacts, such as those shown at 74 in FIGS. 2 and 3 in assembly 70. It should be noted that what might be thought of as the open, or blade-receiving, side of the contacts in assembly 70 faces toward the viewer in FIG. 2, whereas that of the contacts in assembly 68 faces away from the viewer in this figure.

Blade 72 in the switch comprises an elongated tube 76 and a pair of fittings 78, 80 mounted on the opposite ends of the tube. Fitting 78 is suitably fastened to the left end of tube 76 in FIG. 2, and fitting 80 is suitably fastened to the right end of the tube in the figure. These two fittings are substantially the same in construction, and are conventional. The overall length of blade 72 herein is about 7% feet.

Attached to tube 72 substantially centrally between its opposite ends is a mounting 82 which mounts the tube on, and for rotation with, the upper free end of insulator 34 in FIG. 2. With the tube so mounted, its longitudinal axis is disposed at substantially a right angle to the longitudinal axis of insulator 34, with the tube adapted to rotate in a substantially horizontal plane with rotation of the insulator.

Blade 72 is shown in FIGS. 2 and 3 in solid outline in a position with the fittings forming its opposite ends engaging the contacts in contact assemblies 68, 70. With such the case, and as can be seen clearly in FIG. 2, blade 72 and insulators 30, 32 together define a substantially planar triangular zone, containing insulator 34, and having one of its apices adjacent base 28. With the blade in such a position, an electrical connection exists between the contacts in assemblies 68, 70. With rotation of insulator 34 in a clockwise direction about its axis as such is viewed in FIG. 3, blade 72 rotates as indicated by the arrows in this figure to produce simultaneous disengagement of its opposite end fittings and the contacts in assemblies 68, 70. In fragmentary dashed outline in FIG. 3, the blade is shown thus rotated. Obviously, rotation of insulator 34 (and hence of blade 72) in the reverse direction, is effective to produce simultaneous engagement of the blades opposite ends again with the contact assemblies.

Previously mentioned line 18a has its right end in FIGS. 2 and 3 anchored to terminal pad 64 through a conventional connector 84. Similarly, line 18b has its left end in these figures anchored to terminal pad 66 through a connector 86 which is substantially the same in construction as connector 84.

The advantages and desirable features of the switch assembly just described will thus be apparent. The triangular planar configuration proposed for the assembly results in an assembly whose overall construction is extremely simple and compact. Especially contributing to compactness in the assembly is the fact that the lower ends of the insulators therein converge, and join with a relatively small base 28 which accommodates mounting of the assembly on the cross arms in power pole structure. With such the case, only a single pair of cross arms, anchored to one or two power poles, as the particular application dictates, are required to support the proposed switch assembly. As a consequence, and as can be seen in FIG. 1, only a relatively simple, and a very compact, support structure need by employed for the switch mechanism. Such compact construction in the switch assembly also permits ready mounting of a plurality of switch assemblies on a single set of cross arms as is shown in FIG. 1.

While an embodiment of the invention has been described herein, it is appreciated that variations and modifications may be made without departing from the spirit of the invention.

It is claimed and desired to secure by Letters Patent:

1. A high-voltage single-pole double-break switch assembly comprising a base, 7

three elongated insulators, including a pair of outer insulators and an inner insulator, occupying a common plane and having a set of adjacent ends mounted on said base and a set of spaced-apart free ends remote from said base, said insulators diverging from one another progressing away from said base, and

a switch including a pair of contacts each mounted adjacent the free end of a different one of said outer insulators, and an elongated blade mounted intermediate its opposite ends adjacent the free end of said inner insulator for swinging of its opposite ends simultaneously into and out of engagement with said contacts.

2. The switch assembly of claim 1, wherein said outer insulators are rigidly anchored to said base, said blade is rigidly anchored to said inner insulator, and said inner insulator is joumaled on said base for rotation about the inner insulators longitudinal axis.

3. The switch assembly of claim 1, wherein said outer insulators and said blade, with the opposite ends of the latter engaging said contacts, bound a substantially triangular zone, one apex of which is adjacent said base.

4. A high-voltage single-pole double-break switch assembly comprising a base,

first and second elongated insulators occupying a common plane and having a set of adjacent ends anchored to said base and a set of spaced-apart free ends remote from said base, said insulators diverging progressing away from said base,

a third insulator occupying said common plane and positioned substantially centrally intermediate said first and second insulators, said third insulator having one rend journaled on said base for rotation about its own longitudinal axis and'a free end remote from said base, and

a switch including a pair of contacts each mounted adjacent the free end of a different one of said first-mentioned two insulators, and an elongated 

1. A high-voltage single-pole double-break switch assembly comprising a base, three elongated insulators, including a pair of outer insulators and an inner insulator, occupying a common plane and having a set of adjacent ends mounted on said base and a set of spacedapart free ends remote from said base, said insulators diverging from one another progressing away from said base, and a switch including a pair of contacts each mounted adjacent the free end of a different one of said outer insulators, and an elongated blade mounted intermediate its opposite ends adjacent the free end of said inner insulator for swinging of its opposite ends simultaneously into and out of engagement with said contacts.
 2. The switch assembly of claim 1, wherein said outer insulators are rigidly anchored to said base, said blade is rigidly anchored to said inner insulator, and said inner insulator is journaled on said base for rotation about the inner insulator''s longitudinal axis.
 3. The switch assembly of claim 1, wherein said outer insulators and said blade, with the opposite ends of the latter engaging said contacts, bound a substantially triangular zone, one apex of which is adjacent said base.
 4. A high-voltage single-pole double-break switch assembly comprising a base, first and second elongated insulators occupying a common plane and having a set of adjacent ends anchored to said base and a set of spaced-apart free ends remote from said base, said insulators diverging progressing away from said base, a third insulator occupying said common plane and positioned substantially centrally intermediate said first and second insulators, said third insulator having one end journaled on said base for rotation about its own longitudinal axis and a free end remote from said base, and a switch including a pair of contacts each mounted adjacent the free end of a different one of said first-mentioned two insulators, and an elongated blade mounted intermediate its opposite ends adjacent the free end of said third insulator for swinging of its said opposite ends, with rotation of said third insulator, simultaneously into and out of engagement with said contacts, said first and second insulators and said blade, with the opposite ends of the latter engaging said contacts, bounding a substantially triangular zone disposed in said common plane and containing said third insulator, one apex of said zone being adjacent said base, and the other two apices of the zone being adjacent third contacts. 